Hi Chris, there seems to be a category of I guess maybe vinyl cutting type machines that have some software that seems to work ok with full splines in DXF format.

Some people have found that conversion utility helped them get curves into their cutting software even though it only converts full splines and does not do conversion to arcs.

Maybe in those cases the bundled software for the machine is doing arc conversion itself or something like that.

But at any rate I do know that export to DXF with full splines without arc conversion has helped some people for particular CNC work before.

I don't doubt that for other purposes arc conversion would be required - there is a lot of variation between different types of CNC use and different kinds of receiving software.

- Michael